The rapid dynamics of COVID-19 calls for quick and effective tracking of virus transmission chains and early detection of outbreaks, especially in the phase 2 of the pandemic, when lockdown and other restriction measures are progressively withdrawn, in order to avoid or minimize contagion resurgence. For this purpose, contact-tracing apps are being proposed for large scale adoption by many countries. A centralized approach, where data sensed by the app are all sent to a nation-wide server, raises concerns about citizens' privacy and needlessly strong digital surveillance, thus alerting us to the need to minimize personal data collection and avoiding location tracking. We advocate the conceptual advantage of a decentralized approach, where both contact and location data are collected exclusively in individual citizens' "personal data stores", to be shared separately and selectively, voluntarily, only when the citizen has tested positive for COVID-19, and with a privacy preserving level of granularity. This approach better protects the personal sphere of citizens and affords multiple benefits: it allows for detailed information gathering for infected people in a privacy-preserving fashion; and, in turn this enables both contact tracing, and, the early detection of outbreak hotspots on more finely-granulated geographic scale. Our recommendation is two-fold. First to extend existing decentralized architectures with a light touch, in order to manage the collection of location data locally on the device, and allow the user to share spatio-temporal aggregates - if and when they want, for specific aims - with health authorities, for instance. Second, we favour a longer-term pursuit of realizing a Personal Data Store vision, giving users the opportunity to contribute to collective good in the measure they want, enhancing self-awareness, and cultivating collective efforts for rebuilding society.

中文翻译：

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为公民个人提供更多数据、意识和控制，他们将有助于遏制 COVID-19

COVID-19 的快速发展要求快速有效地跟踪病毒传播链并及早发现疫情，尤其是在大流行的第二阶段，即逐步取消封锁和其他限制措施时，以避免或最大限度地减少传染病的死灰复燃. 为此，许多国家/地区正在提议大规模采用联系人跟踪应用程序。应用程序检测到的数据全部发送到全国服务器的集中式方法引发了对公民隐私和不必要的强大数字监控的担忧，从而提醒我们需要尽量减少个人数据收集并避免位置跟踪。我们提倡去中心化方法的概念优势，在这种方法中，联系人和位置数据都仅在个人公民的“